A5087978898- Soil Carbon and Nitrogen Dynamics
- Soil and Water Nutrient Dynamics
- Research in Cotton Cultivation
- Soil erosion and sediment transport
- Irrigation Practices and Water Management
- Agronomic Practices and Intercropping Systems
- Soil Management and Crop Yield
- Hydrology and Watershed Management Studies
- Crop Yield and Soil Fertility
- Wastewater Treatment and Nitrogen Removal
- Legume Nitrogen Fixing Symbiosis
- Rice Cultivation and Yield Improvement
- Planetary Science and Exploration
- Space Exploration and Technology
- Agroforestry and silvopastoral systems
- Astro and Planetary Science
- Rangeland and Wildlife Management
- Phosphorus and nutrient management
- Plant Water Relations and Carbon Dynamics
- Constructed Wetlands for Wastewater Treatment
- Aquatic Ecosystems and Phytoplankton Dynamics
- Pesticide and Herbicide Environmental Studies
- Water Quality and Resources Studies
- Climate change impacts on agriculture
- Nematode management and characterization studies
Mitchell Institute
2022-2025
Texas A&M University
2018-2025
Texas A&M University – Kingsville
2020-2023
Texas A&M University System
2011-2023
Vernon College
2020
Johnson Space Center
2006-2013
University of Arkansas at Fayetteville
2001-2006
United States Department of Agriculture
2005
Agricultural Research Service
2005
National Soil Erosion Research Laboratory
2005
ABSTRACT Currently, several state and federal agencies are proposing upper limits on soil test phosphorus (P), above which animal manures cannot be applied, based the assumption that high P concentrations in runoff due to P. Recent studies show other factors more indicative of from areas where manure is being applied. The original index was developed as an alternative management tool incorporating affecting both source transport objective this research evaluate effects multiple variables...
Core Ideas Soil organic C was two times greater with a no‐tillage rye cover crop system compared conventional tillage (winter fallow) 17 yr after imposing treatments. A rate of gain observed mixed species than in 3‐yr period. Cotton lint yield and gross margins were less tillage. Differences did not exist between the Conservation coupled winter crops may reduce wind erosion North America Great Plains. Although farmers recognize benefits conservation practices, their decision to use is often...
Research has shown that aluminum sulfate (alum) and phosphoric acid greatly reduce ammonia (NH3) volatilization from poultry litter; however, no studies have yet reported the effects of these amendments on field-scale composting litter. The objectives this study were to (i) evaluate NH3 litter by measuring both changes in total nitrogen (N) (ii) potential methods reducing losses Poultry was composted for 68 d first year 92 second year. Eleven treatments screened Year 1, which included an...
<abstract> <b><sc>Abstract.</sc></b> Cotton is one of the major crops cultivated in Texas Rolling Plains region, and it a contributor to regional economy. cultivation this region facing severe challenges due an increase frequency droughts projected decrease rainfall future. Development evaluation deficit irrigation strategies for could potentially conserve water while maintaining cotton yields. In study, Decision Support System Agrotechnology Transfer (DSSAT) Cropping Model (CSM)...
Agriculture provides a direct interface between humans and the (C) cycle is performed on large enough scales to impact climate resiliency regional scales. Carbon in agriculture systems primarily cycled through photosynthesis soil respiration. sequestration occurs when C inputs are greater than losses can be achieved by increasing photosynthetic inputs, reducing respiration, or combination of two. Cotton (Gossypium hirsutum) cropping semi-arid Texas High Plains (THP) receive limited amount...
ABSTRACT A phosphorus (P) index for pastures was developed to write nutrient management plans that determine how much P can be applied a given field. The objectives of this study were (i) evaluate and compare the pastures, particularly source component, an environmental threshold soil test level by conducting rainfall simulations on contrasting soils under various scenarios; (ii) field‐scale watersheds. Poultry litter 12 small plots each six farms based either or runoff evaluated using...
Nitrogen runoff from pastures fertilized with animal manure, such as poultry litter, can result in accelerated eutrophication. The objective of this study was to evaluate the long-term effects grazing management and buffer strips on N litter. A 12-yr conducted 15 small watersheds Booneville, AR, using five practices: continuous grazing, haying, rotational an unfertilized strip, a fenced riparian buffer. Poultry litter applied annually at rate 5.6 Mg ha. Concentrations loads total N, NO-N,...
Abstract Wheat ( Triticum spp.) dominates dryland grain crop production in the North American Great Plains and other regions with semi‐arid steppe climates. A common practice is to alternate winter or spring wheat a 14‐ 21‐mo fallow period allow for soil‐water recharge, despite economic inefficiencies environmental degradation. Replacing non‐cereal seed crops often reduces future yields due increased water stress during fill. The use of annual forages may not have disadvantages associated...
Cotton boll count is an important phenotypic trait that aids in a better understanding of the genetic and physiological mechanisms cotton growth. Several computer vision technologies are available for segmentation. However, estimating number bolls segmented cluster challenging task due to complex shapes bolls. This study proposed combination spectral-spatial supervised machine learning based methods candidate recognition counting from high resolution RGB images obtained unmanned aerial...
Phosphorus inputs into reservoirs include external sources from the watershed and internal reservoir bottom sediments. This study quantified sediment P flux in Lake Eucha, northeastern Oklahoma, USA, evaluated effectiveness of chemical treatment to reduce flux. Six intact sediment-water columns were collected three sites Eucha near channel at depths 10 15 m. Three water each site incubated for 21 d approximately 22 degrees C under aerobic conditions, anaerobic conditions (N2 with 300 ppm...
Identifying management practices that conserve and protect water resources are very important to a wide variety of stakeholders within semiarid environments. The objective this study was develop strategies for transitioning tillage systems in cotton ( Gossypium hirsutum L.) production the Texas Rolling Plains when subsurface drip irrigation (SDI) system. Five regimes (0, 33, 66, 100, 133% evapotranspiration [ET] replacement) four (conventional till, reduced no‐till, no‐till with terminated...
Nitrate (NO) is a major contaminant and threat to groundwater quality in Texas. High-NO used for irrigation domestic purposes has serious environmental health implications. The objective of this study was evaluate spatio-temporal trends NO concentrations Texas on county basis from 1960 2010 with special emphasis the Rolling Plains (TRP) using Water Development Board's database. Results indicated that have significantly increased several counties since 1960s. In 25 counties, >30% observations...
Abstract . Interest in cover crops has been increasing the Texas Rolling Plains (TRP) region, mainly to improve soil health. However, there are concerns that could potentially reduce water and thereby affect yield of subsequent cash crops. Previous field studies from this region have demonstrated mixed results, with some showing a reduction crop due others indicating no significant impact on cotton fiber yield. The objectives study were (1) evaluate CROPGRO-Cotton CERES-Wheat modules within...
Core Ideas Soil nitrate was lower due to a cereal rye cover crop during the active growing season. Infiltration greater for no‐till with than conventional tillage. After 17 years, had soil organic C tillage in surface layers. did not differ between and subsurface No‐till has potential alleviate resistance compaction at Adoption of conservation cotton cropping systems lags well behind other major crops United States. The Texas High Plains region is largest cotton‐producing States an area...
Introduction Nitrous oxide (N 2 O) emission from soil is a major concern due to its contribution global climate change and function as loss mechanism of plant-available nitrogen (N) the soil. This especially true in intensive agricultural soils with high rates N fertilizer application such those on semi-arid Southern High Plains, USA. Methods study examined emissions O, pore-space concentrations O nitric (NO), chemical properties, water content, genetic potential for cycling five years after...
It is evident that legume root nodules can accommodate rhizobial and non-rhizobial bacterial endophytes. Our recent nodule microbiome study in peanuts described small harbor diverse To understand their functional role, we isolated 87 indigenous endophytes from of field-grown peanut roots characterized them at molecular, biochemical, physiological levels. The amplified 16S rRNA genes phylogenetic analysis these isolates revealed a wide variety microorganisms related to the genera Bacillus,...
Soil phosphorus (P) is an increasingly important consideration in the development of P-based nutrient management strategies. The objectives this study were to (i) obtain baseline information on soil P variability pastures amended with animal waste, (ii) examine if current sampling recommendations related number subsamples adequately reduce uncertainty acceptable limits, and (iii) implications estimates implementing a threshold 150 mg kg(-1). Grid samples collected from 12 pastures. was...